study/work retreat (Colombo)

I have been living the past 7 years in Nepal. I am currently in India and planning to spend December in Sri Lanka. Unfortunately I am not coming for holidays. I need to do personal work and study, therefore I need a quiet place, with nature surroundings, wi-fi so I can work, meals easily available, in affordable price around 20. Protected content Sri Lankan Rupies. A home-stay is also a welcomed option. If anyone has suitable suggestions that would be very beneficial.